This invention generally relates to chute loading systems, and more particularly, to systems including chutes pivoted into and out of loading position, and capable of rapid chute positioning and flow control, including incremental flow adjustment.
Prior art chutes are known for use in loading facilities for directing the flow of material from large overhead storage bins into hopper cars positioned below. A common type of loading chute is capable of lateral and telescopic vertical movement for positioning above a hopper car. For lateral movement, such prior art chutes are rollably secured to an independent overhead frame structure. The chute generally includes a gate valve positioned adjacent the top inlet opening of the chute. Generally speaking, these prior art chutes are effective for rapid material loading after proper alignment with the loading vehicle; however, such prior art chutes require precise lateral positioning followed by telescopic lowering of the chute to a proper discharge height, often a time consuming process. In addition, when the car is substantially filled it is difficult to achieve precise topping off without spilling material.
Loading chutes capable of pivoting into discharge position are known. Such prior art chutes generally offer the advantage of fast overhead positioning and rapid material flow. Often, however, similar difficulties are encountered in relation to precise topping off as with telescoping chutes. Some attempts have been made to improve flow control as car loading capacity is achieved. One such attempt is disclosed in the prior U.S. Pat. No. 1,863,028 of Pardee, Jr. wherein a pivoting chute includes a plurality of retarder plates positioned within the flow path of the chute. As material is loaded in the car the chute is gradually raised thereby projecting the retarders into the flow path to reduce the flow. A separate chute is positioned adjacent the main chute for topping off the car with material discharged from a separate auxiliary outlet. Although better control of material flow is achieved with this device, such control requires constant, gradual pivoting of the chute structure in addition to requiring a separate topping off chute and discharge outlet structure.